20104715857 has 2 divisors, whose sum is σ = 20104715858. Its totient is φ = 20104715856.

The previous prime is 20104715849. The next prime is 20104715861. The reversal of 20104715857 is 75851740102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20087109441 + 17606416 = 141729^2 + 4196^2 .

It is a cyclic number.

It is not a de Polignac number, because 20104715857 - 2³ = 20104715849 is a prime.

It is not a weakly prime, because it can be changed into another prime (20104715837) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10052357928 + 10052357929.

It is an arithmetic number, because the mean of its divisors is an integer number (10052357929).

Almost surely, 2^20104715857 is an apocalyptic number.

It is an amenable number.

20104715857 is a deficient number, since it is larger than the sum of its proper divisors (1).

20104715857 is an equidigital number, since it uses as much as digits as its factorization.

20104715857 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 78400, while the sum is 40.

The spelling of 20104715857 in words is "twenty billion, one hundred four million, seven hundred fifteen thousand, eight hundred fifty-seven".